At least 813 persons have died in northern Nigeria since the outbreak of meningitis in November last year.
The eruption of the killer disease and its speedy lethal effect had generated massive concern from across and outside Nigeria. But due to the general lack of adequate knowledge on the disease, many Nigerians, including public officials ascribed superstitious essence to the epidemic.
It could be recalled that the Governor of Zamfara, Abdulaziz Yari, in whose state the outbreak began, described the disease as divine punishment for the many sins of the people, with his comment drawing on him an avalanche of condemnations from across the country.
Pushing aside the governor’s view, Miriam Alía, a vaccination and outbreak advisor at Medicine Sans Frontier (MSF), has explained why Meningitis is prevalent in Nigeria and neighbouring Niger Republic.
Ms. Alia, who is one of the two MSF staff working in the International Coordinating Group (ICG) on Vaccine Provision, said though people anywhere in the world can be infected with the disease, environmental factors are significant in making it an epidemic.
“People can succumb to meningitis all year round, but this region’s dry and windy climate between December and May allows it to spread even more”, she said.
She explained that the contamination could easily be spread through “droplets of saliva” which is easily conveyed in the type of dry wind in Nigeria that irritates the throat.
But she said with the arrival of the rainy season, transmission is reduced and “the number of cases decreases exponentially”. This suggests that the current reduction in the spread of the epidemics may not be totally due to the medical interventions provided by the Nigerian government.
She said the best solution is to immunize people, “just like we do for measles”. But she pointed out that vaccination for meningitis is more complex than for other killer diseases like measles.
“Unlike measles, which has a single type of vaccine that works well, there are many different vaccines for meningitis. Firstly, there are different types of meningitis and you need to identify the serogroup that causes the outbreak: A, B, C, W135, X or Y. Some vaccines only work for one serogroup, whereas others can work for up to four. Unfortunately, there is insufficient vaccine production to preventively vaccinate against all types of meningitis.”
On the type of vaccines that are readily available for Meningitis, Ms. Alía said the disease has two types of vaccines – the affordable ones whose efficacy last for only three years and the expensive ones that last a long time.
“On the one hand, we have polysaccharide vaccines – a first generation of vaccines – that are inexpensive, simple to produce and prevent transmission. However, they are only effective for three years and also don’t prevent healthy carriers. We also have conjugates –a new generation of vaccines– that are also effective in healthy carriers and provide a more prolonged immunity, but they are more expensive.”
She said the first conjugate vaccine used on a large scale was MenAfriVac developed by the Serum Institute of India, which was very cheap and effective and managed to halt the explosive outbreaks of meningitis A that occurred in the region in the 1990s and 2000s.
“Thanks to the collaboration of the Bill Gates Foundation, UNICEF and the WHO, mass vaccination campaigns were developed for people aged between 1 and 30 years old, and it is progressively being introduced into routine vaccination schedules in these countries. It is estimated that more than 260 million people have been vaccinated with MenAfriVac since 2009.”
She further explained that the mass production of MenAfriVac was only done for type-A meningitis. The type C meningitis that occurred in Nigeria in recent years was not anticipated.
“After the great success with the meningitis A vaccine campaign, we did not expect similar epidemics of other serogroups,” she said.
“In 2013 and 2014, however, there were already meningitis C outbreaks in northwest Nigeria, and in 2015 there was a huge outbreak affecting Nigeria and Niger. In addition, this was from a highly virulent serogroup C.
“We had never dealt with a meningitis C outbreak as big as this, and the production of vaccines was insufficient. Nor do we have a long-term protection vaccine that is as cheap as MenAfriVac for meningitis C.”
Ms. Alía however allayed the fears over lack of appropriate vaccine for meningitis C as she said “right now, the Serum Institute of India is working on a vaccinated pentavalent conjugate (A, C, Y, W-135, X) which, in theory, will be available for 2020.
“If it is as effective and safe as the MenAfriVac—which can also be used for four days outside of the cold chain—we will be dealing with a super vaccine. The perverse effect of this is that other laboratories are not going to produce many vaccines, because if they don’t use them beforehand they know that they will not have a market for them.”
Until that is done, Ms. Alía said Nigeria and other African countries may have to continue contending with Meningitis C due to insufficient vaccines.
“After the meningitis C outbreak of 2015, the ICG established a minimum stock of five million vaccinations for serogroup C,” she said.
“However, we didn’t reach that figure in 2016 or this year. There isn’t as much production and laboratories will not risk producing a vaccine that is sold only if there is an epidemic and has a market only until 2020.
“Thus, the available vaccines can only be used reactively when an outbreak is declared, and not preventively in risk areas in order to avoid it. This year, epidemics have been declared in eastern and western Nigeria and various parts of Niger, and there has also been a small outbreak in Togo.
“The ICG has already supplied several shipments of meningitis C vaccines to Niger and Nigeria this year. In some cases, these are polysaccharides, and for the first time, there are also conjugates.
“But we have had to reduce the number of vaccines from the original request or reduce the target age group, because for yet another year we are dealing with the problem of vaccine shortage, despite having purchased all the available stock. The epidemiological criteria that regulate where and which population group to vaccinate are very strict in order to respect the principles of equity on which the ICG is based.”
Ms. Alía said meningitis causes an inflammation of the meninges, the fine membranes that cover the brain and the spinal cord. The disease may be of viral or bacterial origin, but while viral meningitis is usually benign, bacterial meningitis (caused by the bacterium Neisseria meningitidis) is serious and can be fatal.
According to the World Health Organization, around one million suspected cases have been reported in the last 20 years and 100,000 people have died. The most affected region is Africa.
According to official estimates, the death toll from the recent meningitis in northern Nigerian is at least 1,114 with Zamfara having the highest casualty figure.